diff --git a/lib_com/ivas_rotation_com_fx.c b/lib_com/ivas_rotation_com_fx.c
index 4106e5d059bbb2f49259c6b8601781547dd48b3f..5fc6261a955b8f0fbee67a48d693230994521342 100644
--- a/lib_com/ivas_rotation_com_fx.c
+++ b/lib_com/ivas_rotation_com_fx.c
@@ -113,7 +113,7 @@ void Copy_Quat_fx(
 
 
 /*-------------------------------------------------------------------------
- * Scale_Quat_fx()
+ * modify_Quat_q_fx()
  *
  * Quaternion q factor modification
  *------------------------------------------------------------------------*/
@@ -124,10 +124,18 @@ void modify_Quat_q_fx(
     Word16 q_new                    /* i  : quaternion describing the rotation             */
 )
 {
+#ifdef FIX_BASOP_2361_OTR
+    Word16 shift = sub( q_new, in_quat->q_fact );
+    out_quat->w_fx = L_shl_sat( in_quat->w_fx, shift ); // q_new
+    out_quat->x_fx = L_shl_sat( in_quat->x_fx, shift ); // q_new
+    out_quat->y_fx = L_shl_sat( in_quat->y_fx, shift ); // q_new
+    out_quat->z_fx = L_shl_sat( in_quat->z_fx, shift ); // q_new
+#else
     out_quat->w_fx = L_shl_sat( in_quat->w_fx, sub( q_new, in_quat->q_fact ) ); // q_new
     out_quat->x_fx = L_shl_sat( in_quat->x_fx, sub( q_new, in_quat->q_fact ) ); // q_new
     out_quat->y_fx = L_shl_sat( in_quat->y_fx, sub( q_new, in_quat->q_fact ) ); // q_new
     out_quat->z_fx = L_shl_sat( in_quat->z_fx, sub( q_new, in_quat->q_fact ) ); // q_new
+#endif
     out_quat->q_fact = q_new;
     return;
 }
@@ -147,12 +155,19 @@ void modify_Rmat_q_fx(
 )
 {
     Word16 j, k;
+#ifdef FIX_BASOP_2361_OTR
+    Word16 shift = sub( q_new, q_cur );
+#endif
 
     FOR( j = 0; j < 3; j++ )
     {
         FOR( k = 0; k < 3; k++ )
         {
+#ifdef FIX_BASOP_2361_OTR
+            Rmat_out[j][k] = L_shl( Rmat_in[j][k], shift );
+#else
             Rmat_out[j][k] = L_shl( Rmat_in[j][k], sub( q_new, q_cur ) );
+#endif
             move32();
         }
     }
diff --git a/lib_com/options.h b/lib_com/options.h
index 51bd5a3f340e3f8fc8a819cfe3a960f785297a6c..0ea316a82a8cdacb4562394ba7ad6b5cd236a9bd 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -118,6 +118,7 @@
 #define FIX_2250_LARGE_DIFFERENCES_BETWEEN_BASOP_AND_FLOAT  /* Dolby: Issue 2250:  random vector generation in GenShapedSHBExcitation() */
 #define FIX_2338_HARM_GSC_GAIN_COMP                     /* VA: basop issue 2338: harmonization of band gain computation for both EVS and IVAS */
 #define FIX_BASOP_2317_UNINIT_VALUE_IN_STEREO_CNG       /* Eri: Basop issue 2317: Uninitialized value read in case of DTX and BW switching   */
+#define FIX_BASOP_2361_OTR                              /* FhG: Basop issue 2361: Orientation tracking tests for equivalent rotations fail */
 #define FIX_1283_STEREO_DFT_COLLAPSE                    /* FhG: float issue 1283: fix for critical issue with DFT stereo core coder */
 #define FIX_2379_REMOVE_previoussynth_fx_32             /* VA: basop issue 2379: remove duplicated buffer st->previoussynth_fx_32[] */
 #define FIX_2396_CONSTANT_STRIDE_IN_TC_BUFFER           /* FhG/VA: basop issue 2396: keep TC channel pointers in one constant place during decoding and rendering */
diff --git a/lib_rend/ivas_orient_trk_fx.c b/lib_rend/ivas_orient_trk_fx.c
index 571106b6c160d57eaa4926e61b682222313a4c21..18fabc03252f67e43a4ee01e1fcfb9b8624b57b5 100644
--- a/lib_rend/ivas_orient_trk_fx.c
+++ b/lib_rend/ivas_orient_trk_fx.c
@@ -482,11 +482,21 @@ static Word32 VectorLength_fx(
     IVAS_VECTOR3 p,
     Word16 *q_fact )
 {
+#ifdef FIX_BASOP_2361_OTR
+    Word16 sqrt_e;
+    Word32 result_fx;
+    result_fx = Madd_32_32( Madd_32_32( Mpy_32_32( p.x_fx, p.x_fx ), p.y_fx, p.y_fx ), p.z_fx, p.z_fx );
+    sqrt_e = shl( sub( 31, p.q_fact ), 1 ); /* convert Q to E */
+
+    result_fx = Sqrt32( result_fx, &sqrt_e );
+    *q_fact = sub( 31, sqrt_e ); /* back to Q again */
+#else
     Word32 result_fx = 0;
     move32();
     result_fx = L_add( L_add( Mpy_32_32( p.x_fx, p.x_fx ), Mpy_32_32( p.y_fx, p.y_fx ) ), Mpy_32_32( p.z_fx, p.z_fx ) ); // // Q: ( p1.q_fact + p2.q_fact ) - 31
 
     *q_fact = sub( add( p.q_fact, p.q_fact ), 31 );
+#endif
     move16();
     return result_fx;
 }
@@ -702,7 +712,14 @@ ivas_error ivas_orient_trk_SetReferenceRotation_fx(
         Euler2Quat_fx( deg2rad_fx( refRot.x_fx ), deg2rad_fx( refRot.y_fx ), deg2rad_fx( refRot.z_fx ), &pOTR->refRot );
         modify_Quat_q_fx( &pOTR->refRot, &pOTR->refRot, Q29 );
     }
-    pOTR->refRot = refRot;
+#ifdef FIX_BASOP_2361_OTR
+    ELSE
+    {
+#endif
+        pOTR->refRot = refRot;
+#ifdef FIX_BASOP_2361_OTR
+    }
+#endif
 
     return IVAS_ERR_OK;
 }
@@ -824,11 +841,16 @@ ivas_error ivas_orient_trk_SetReferenceVector_fx(
             return IVAS_ERR_WRONG_PARAMS;
     }
 
+#ifdef FIX_BASOP_2361_OTR
+    Word16 tmp_q;
+    acousticFrontVectorLength = VectorLength_fx( acousticFrontVector, &tmp_q );
+#else
     Word16 accoustic_q = acousticFrontVector.q_fact;
     move16();
     acousticFrontVectorLength = VectorLength_fx( acousticFrontVector, &acousticFrontVector.q_fact );
     acousticFrontVector.q_fact = accoustic_q;
     move16();
+#endif
     /* if the length is zero, the user has entered insensible listener and reference positions */
     IF( LE_32( acousticFrontVectorLength, 0 ) )
     {
@@ -889,6 +911,18 @@ ivas_error ivas_orient_trk_Process_fx(
             /* Reset average orientation   */
             pOTR->absAvgRot = absRot;
 
+#ifdef FIX_BASOP_2361_OTR
+            Word16 scale_e;
+            Word16 tmp;
+            tmp = BASOP_Util_Divide3232_Scale( PI2_C_ADP_RATE_Q31, updateRate_fx, &scale_e );
+            scale_e = add( scale_e, 23 - 31 ); /* updateRate_fx is hardcoded in caller to Q23 */
+
+            /* sin(x) is approx x for small x */
+            pOTR->alpha_fx = L_deposit_h( tmp );
+            move32();
+            pOTR->Q_alpha = sub( Q31, scale_e );
+            move16();
+#else
             Word16 scale_e;
             Word32 div;
             div = L_deposit_h( BASOP_Util_Divide3232_Scale( pOTR->centerAdaptationRate_fx, updateRate_fx, &scale_e ) );
@@ -897,6 +931,7 @@ ivas_error ivas_orient_trk_Process_fx(
             // here div value is less so we can use sandwitch rule of sine//
             pOTR->alpha_fx = div;
             move32();
+#endif
             /* Compute relative orientation = (absolute orientation) - (reference orientation) */
             QuaternionInverse_fx( pOTR->refRot, &pOTR->trkRot );
             QuaternionProduct_fx( pOTR->trkRot, absRot, &pOTR->trkRot );
@@ -950,6 +985,8 @@ ivas_error ivas_orient_trk_Process_fx(
             cutoff_prod = L_shl( cutoff_prod, temp_diff );
             /* Compute adaptivity cutoff frequency: interpolate between minimum (center) and maximum (off-center) values */
             cutoffFrequency_fx = L_add( pOTR->centerAdaptationRate_fx, cutoff_prod ); // Q31
+
+            /* Compute filter coefficient corresponding to desired cutoff frequency */
             cutoff_prod = Mpy_32_32( cutoffFrequency_fx, PI2_C_Q28 );
             q_cutoff_prod = ( ( 31 + 28 ) - 31 );
             temp_result = BASOP_Util_Divide3232_Scale( cutoff_prod, updateRate_fx, &result_e );
diff --git a/lib_util/vector3_pair_file_reader.c b/lib_util/vector3_pair_file_reader.c
index c6758b6b1a5030d40316a8e6c0f6d862669f815e..27a21d21e8904a62acf01681ec8da719f0ab268d 100644
--- a/lib_util/vector3_pair_file_reader.c
+++ b/lib_util/vector3_pair_file_reader.c
@@ -114,8 +114,13 @@ ivas_error Vector3PairFileReader_read(
     pSecond->y = y2;
     pSecond->z = z2;
 
+#ifdef FIX_BASOP_2361_OTR
+    pFirst->q_fact = 27;  // Q27
+    pSecond->q_fact = 27; // Q27
+#else
     pFirst->q_fact = 29;  // Q29
     pSecond->q_fact = 29; // Q29
+#endif
     pFirst->x_fx = floatToFixed_32( pFirst->x, pFirst->q_fact );
     pFirst->y_fx = floatToFixed_32( pFirst->y, pFirst->q_fact );
     pFirst->z_fx = floatToFixed_32( pFirst->z, pFirst->q_fact );